
var pow = Math.pow, sqrt = Math.sqrt, sin = Math.sin, cos = Math.cos, PI = Math.PI, c1 = 1.70158, c2 = c1 * 1.525,
    c3 = c1 + 1, c4 = 2 * PI / 3, c5 = 2 * PI / 4.5;

function bounceOut(x) {
    var n1 = 7.5625, d1 = 2.75;
    if (x < 1 / d1) {
        return n1 * x * x
    } else if (x < 2 / d1) {
        return n1 * (x -= 1.5 / d1) * x + .75
    } else if (x < 2.5 / d1) {
        return n1 * (x -= 2.25 / d1) * x + .9375
    } else {
        return n1 * (x -= 2.625 / d1) * x + .984375
    }
}
$.extend( $.easing,
    {
        easeOutExpo: function (x, t, b, c, d) {
            return (t==d) ? b+c : c * (-Math.pow(2, -10 * t/d) + 1) + b;
        },
        easeOutBounce: function (x, t, b, c, d) {
            if ((t/=d) < (1/2.75)) {
                return c*(7.5625*t*t) + b;
            } else if (t < (2/2.75)) {
                return c*(7.5625*(t-=(1.5/2.75))*t + .75) + b;
            } else if (t < (2.5/2.75)) {
                return c*(7.5625*(t-=(2.25/2.75))*t + .9375) + b;
            } else {
                return c*(7.5625*(t-=(2.625/2.75))*t + .984375) + b;
            }
        },
        easeInQuad: function (x) {
            return x * x
        }, easeOutQuad: function (x) {
            return 1 - (1 - x) * (1 - x)
        }, easeInOutQuad: function (x) {
            return x < .5 ? 2 * x * x : 1 - pow(-2 * x + 2, 2) / 2
        }, easeInCubic: function (x) {
            return x * x * x
        }, easeOutCubic: function (x) {
            return 1 - pow(1 - x, 3)
        }, easeInOutCubic: function (x) {
            return x < .5 ? 4 * x * x * x : 1 - pow(-2 * x + 2, 3) / 2
        }, easeInQuart: function (x) {
            return x * x * x * x
        }, easeOutQuart: function (x) {
            return 1 - pow(1 - x, 4)
        }, easeInOutQuart: function (x) {
            return x < .5 ? 8 * x * x * x * x : 1 - pow(-2 * x + 2, 4) / 2
        }, easeInQuint: function (x) {
            return x * x * x * x * x
        }, easeOutQuint: function (x) {
            return 1 - pow(1 - x, 5)
        }, easeInOutQuint: function (x) {
            return x < .5 ? 16 * x * x * x * x * x : 1 - pow(-2 * x + 2, 5) / 2
        }, easeInSine: function (x) {
            return 1 - cos(x * PI / 2)
        }, easeOutSine: function (x) {
            return sin(x * PI / 2)
        }, easeInOutSine: function (x) {
            return -(cos(PI * x) - 1) / 2
        }, easeInExpo: function (x) {
            return x === 0 ? 0 : pow(2, 10 * x - 10)
        }, easeInOutExpo: function (x) {
            return x === 0 ? 0 : x === 1 ? 1 : x < .5 ? pow(2, 20 * x - 10) / 2 : (2 - pow(2, -20 * x + 10)) / 2
        }, easeInCirc: function (x) {
            return 1 - sqrt(1 - pow(x, 2))
        }, easeOutCirc: function (x) {
            return sqrt(1 - pow(x - 1, 2))
        }, easeInOutCirc: function (x) {
            return x < .5 ? (1 - sqrt(1 - pow(2 * x, 2))) / 2 : (sqrt(1 - pow(-2 * x + 2, 2)) + 1) / 2
        }, easeInElastic: function (x) {
            return x === 0 ? 0 : x === 1 ? 1 : -pow(2, 10 * x - 10) * sin((x * 10 - 10.75) * c4)
        }, easeOutElastic: function (x) {
            return x === 0 ? 0 : x === 1 ? 1 : pow(2, -10 * x) * sin((x * 10 - .75) * c4) + 1
        }, easeInOutElastic: function (x) {
            return x === 0 ? 0 : x === 1 ? 1 : x < .5 ? -(pow(2, 20 * x - 10) * sin((20 * x - 11.125) * c5)) / 2 : pow(2, -20 * x + 10) * sin((20 * x - 11.125) * c5) / 2 + 1
        }, easeInBack: function (x) {
            return c3 * x * x * x - c1 * x * x
        }, easeOutBack: function (x) {
            return 1 + c3 * pow(x - 1, 3) + c1 * pow(x - 1, 2)
        }, easeInOutBack: function (x) {
            return x < .5 ? pow(2 * x, 2) * ((c2 + 1) * 2 * x - c2) / 2 : (pow(2 * x - 2, 2) * ((c2 + 1) * (x * 2 - 2) + c2) + 2) / 2
        }, easeInBounce: function (x) {
            return 1 - bounceOut(1 - x)
        }
    });

